Function clippy_lints::format::get_argument_fmtstr_parts

pub fn get_argument_fmtstr_parts<'a, 'b>(cx: &LateContext<'a, 'b>,
                                         expr: &'a Expr)
                                         -> Option<Vec<InternedString>>

Returns the slice of format string parts in an Arguments::new_v1 call. Public because it's shared with a lint in print.rs.